Brassiere underwires have been provided heretofore in a variety of configurations (see especially U.S. Pat. Nos. 4,201,220; 4,153,062; 4,133,316; 3,562,802 and 3,035,584).
In all of these publications, underwires are described which are of substantially uniform cross section and thickness over the entire length of the generally U-shaped underwire from tip to tip thereof.
Brassiere underwires form stays which impart, shape to or retain the shape of the cup of the brassiere and are generally received in a tubular fabric formation along the lower edge of the cup. That tubular formation or pocket can be formed by stitching. To prevent undesired movement of the underwire stay, it is known to form the stay with sewing flanges which can easily be pierced by a sewing needle and which allow the stay to be fixed in that tubular pocket. Reference can be had, in this regard, to U.S. Pat. No. 4,235,240 which provides such sewing flanges both along the inner and outer sides of the U-shaped underwire or forms the sewing flange so that it extends over the entire length of the underwire. Neither arrangement has been found to be fully satisfactory. The flanges on both the inner and outer sides of the underwire, even where flexibility is promoted by notching those flanges or making them discontinuous, have been found to make the underwire incapable of bending out of its plane to a sufficient degree and where the flanges extend to the tips of the underwire, the underwire has proved to be uncomfortable to the wearer. For that reason, sewing flanges along the underwire have not been found to be acceptable heretofore.